Technical Field of the Invention
The present invention relates generally to digital display systems used with vehicles, and more particularly a digital display system including a front-facing camera and rear digital display.
Description of the Related Art
The safe operation of motor vehicles is of primary importance. In particular, vehicles create visual obstructions for other trailing or following vehicles and thereby create a potentially dangerous environment to drive in. This is particularly the case where a view obstructing vehicle is large, such as a bus or truck.
There are existing prior art systems that seek to address such safety concerns that make use of video cameras and networked vehicles. In one such prior art system, forward-looking cameras are mounted on or near the windshields of large or long vehicles. These cameras then stream live video images of the road ahead, wirelessly to a receiver in an appropriately-equipped trailing or following vehicle. The trailing/following vehicle may then process the live video images for presentation on a transparent LCD display which is integrated into the trailing/following vehicle's windshield.
In another prior art system, a two video camera arrangement is required—one on the leading/view-blocking vehicle, and a second camera on any (and all) vehicles wising to use the “see-through” system. This system is a range-sensitive system which requires users to be relatively close behind the leading/view-blocking vehicle. At a predetermined distance, imagery from both the forward vehicle's camera and the rear vehicle's camera is blended using a special algorithm for display on a Heads-Up Display (HUD) in the following vehicle's windshield. Here, pixels from the leading vehicle's camera replace pixels from the rear vehicle's camera to create an illusion that the leading/view-blocking vehicle appears to become transparent.
The visual technique has some effectiveness but it only functions when the vehicles are within a certain range of each other. Additionally, there are dangers that the processed image presented on the following vehicle's windshield HUD makes the true image of the leading vehicle almost entirely vanish. Such a lack of visual definition could cause a misreading (especially during actual driving, lighting or weather conditions), and perhaps cause accidents.
The above prior art systems have potentially other serious drawbacks or limitations. One such drawback is transmission latency. Because the image is transmitted wirelessly from a leading vehicle to a following vehicle where it is then processed and displayed on the inside of the following vehicle's windshield, there is a delay in the presented image relative to the real world condition. This may be enough to make an oncoming vehicle (such as in a passing lane) appear further away than it actually is. Such latency can cause a head-on vehicle accident or a dangerous situation with pedestrians.
View alignment is another drawback. The viewing vehicle driver must keep his/her eyes (and therefor point of view) within specific physical parameters to assure that the super-imposed images on the LCD display remains properly aligned with his/her true rear-end view of the leading vehicle. This activity may require much effort on the part of the following vehicle driver. Failure to have the proper alignment or vehicle relative movement can result in image shifts causing significant undesirable and distractive feedback.
Moreover, depth of field is another drawback. A driver preparing to pass must focus his/her eyes on the vehicle to be passed, the surrounding environment, and additionally on the much closer shifting image frame on the LCD display which is attached to his/her windshield. This represents an uncomfortable adjustment in focus and depth of field at a time clear viewing, sound judgment and rapid decision-making are critical.
The prior art systems may position a thick black, snap-adjust reference frame on the viewing LCD to define the area in which the video image appears and changes. As the two vehicles move relative to one another in three dimensions, the black frame snap-adjusts to its revised position and the mere presence of such movement with its associated blockage of the driver's true view can be both distractive and dangerous.
The prior art systems demand that any and all vehicles using the systems be fitted with either cameras and transmitters (the leading/presenting vehicles), or with receivers, processors and a transparent LCD windshield video Heads-Up Display (HUD) in order to work.
Another drawback of the prior art is related to tampering/hacking of transmitted images and/or interference. Because the prior art requires V2V Dedicated Short Range Communication (DSRC) between involved vehicles, the system is subject to wireless interference, dropouts, jamming or deliberate hacking (in addition to latency). It is also conceivable that images from a camera on yet a second or third transmitting vehicle could be inadvertently received—or received by multiple vehicles within range, including vehicles which may be traveling in opposite directions. Such issues could have serious unintended consequences.
Therefore, there is a need in the art for an improved display system in comparison to the prior art. Various aspects of the present invention address these particular needs, as will be discussed in more detail below.